In practicing dentistry it is often necessary to precisely position small quantities of material in difficult to reach locations within a patient's mouth. Some of these materials are often difficult to work with because Accordingly there have been many devices developed to aid the dentist or dental practitioner in the placement of different dental materials. One such invention is disclosed in U.S. Pat. No. 5,489,207 entitled “Dental Cartridge Extruder with Rigid Drop in Front End”, issuing to Dragan et al on Feb. 6, 1996. Therein disclosed is a manual dental extruder or syringe used in combination with a dental cartridge, capsule, or ampoule for extruding viscous dental material, which is herein incorporated by reference.
Additionally in dentistry various capsules or tips have been developed for specific applications. One such capsule is disclosed in U.S. Pat. No. 5,052,927 entitled “Syringe and Disposable Capsule with Cannula for Use Therewith” issuing to Discko, Jr., on Oct. 1, 1991. Therein disclosed is a capsule for dispensing a dental material having a metal cannula thereon permitting precise placement of the dental material.
Another application for a tip is disclosed in U.S. Pat. No. 5,876,384 entitled “Micro Aspirator” issuing to Dragan et al on Mar. 2, 1999. Therein disclosed is an aspirating tip placed on a flexible tube for removing blood, debris and fluids from around a small surgical site.
Another dental cartridge intended for a specific application is disclosed in U.S. Pat. No. 6,135,771 entitled “Dental Cartridge Having an Attachable Delivery Portion” issuing to Dragan et al on Oct. 24, 2000. Therein disclosed is a dental cartridge or capsule having a body portion and a delivery portion or a cap with a metal cannula. The dental cartridge permits the mixing of a first component, typically a powder, and a liquid component of dental material prior to dispensing.
While these prior dental devices have made dentistry easier for the practicing dentist in their particular or specific areas of application, there is a continuing need to develop specialized delivery systems for specific dental materials so as to make dentistry easier. The reactivity or caustic nature of some dental materials to metal has created problems in storing these dental materials in a unit dose capsule designed for precise placement with a metal cannula. Some dental materials, such as material containing chemicals that may react with metal, have been difficult to store and dispense. For example, aluminum chloride may be used as a component in a dental material. Aluminum chloride will react with metal if maintained in contact or in close proximity with the metal for a relatively long time. There have been continuing problems using a unit dose container having a metal cannula containing a dental material that may react with the metal cannula. As a result, the dental material may become unusable or may cause undesirable effects such as discoloration or a failure to perform as desired. Therefore, there is a need for a specialized delivery system that permits the storage of a unit dose of potentially reactive dental material that can be dispensed precisely with a metal cannula.